In data processing systems such as distributed computer systems wherein nodes comprise multiple memories, problems occur when it is desirable to access the same data by independent nodes. Multiple copies may be replicated across different nodes. However, problems occur when updates to the objects occur. Maintaining consistent replicas of the objects can be difficult.
By way of example only and not intended to be a comprehensive list, some types of distributed computing system that may experience this type of problem include Web-based systems, distributed memory multiprocessors, distributed file systems, and distributed databases. Those ordinarily skilled in the art associated with each of these exemplary systems will readily appreciate how maintaining consistent replicas of objects can be difficult.
There is thus a need to for techniques for maintaining consistent replicas of data.